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jfruh (300774) writes "Graphene, a carbon-based crystalline lattice that is extremely strong, lightweight, and an excellent conductor of electricity and heat, is coveted as a potential base for semiconductor chip design, and Samsung, working with the Sungkyungkwan University School of Advanced Materials Science and Engineering, has claimed a big jump towards that goal. With IBM also making progress in this realm, the days of silicon could actually be numbered."

Producing them cheaply enough to rival chips made of processed sand is another matter entirely. Anyone remember gallium arsenide chips that were going to eat silicon for lunch back in the 80s? Yeah , well.... still niche.

Because silicon dropped in price rather dramatically.I don't really see any process on the horizon that will cause another drop like that. It would require a break through making = 22nm fabs much cheaper to build and maintain.

If they made a significant break through where they are competitive, then things will change fast.The demand for more efficient chips has never been higher.

Silicon has always been cheaper, not just recently. Any fancy substrate or switch technology will be unusable as a replacement for silicon if it can't at least approach the density of silicon circuits. We can manufacture extremely complex circuits using the very simple procedures of silicon crystal growing, doping, photolithography, and epitaxy. The moderate cost of modern ICs in the middle of the synchronous price-per-component curve (as per Moore's law) is the result of the combination of these simple procedures (which are ridiculously simplistic when it comes to simple components) with doing them at extreme geometrical complexities (which is *the* thing that makes ICs expensive). Even if you could demonstrate a single graphene switch today, you would still be where Jean Hoerni's planar silicon transistor was in 1960. Now find out how this supposedly very tough material can be either deposited and grown into proper shapes or substractively machined at nanoscale, and all that at high speeds needed for mass IC manufacture.

OR... they could pull off a 16bit chip that can withstand temps up to 3000 degrees and is impervious to EMP attacks and you have the defense industry paying you all the money you want to figure it out.

The problem is that transistors are thermoelectric devices. You switch them on and off by heating them up to change their conductivity. Silicon chips can withstand temperatures well beyond the point at which the plastic packages they are mounted to break down, but that temperature is also well beyond their switching point, making them useless as a computational device.

If you could produce a semiconductor that was useful at 3000F, then that would be its normal operating temperature, and you would need to feed it a high enough core voltage to allow it to heat itself up to that temperature to switch.

Yes. That is how a semiconductor functions. At low temperatures, you're below the band gap, requiring energy be supplied to excite the atoms, bump electrons to a higher shell, open holes, and increase conductivity. At high temperatures, you're above the band gap, and you can't function because you're always a conductor.

That is correct. When you excite the outer shell of electrons, causing them to jump to a higher energy state, and allow conduction, you have added energy (heat) to the system. However you want to go about supplying that heat to the system, you have heated it up, and heating it up has in turn make the semiconductor conductive. It is a thermally regulated electric device.

How did this get rated +4, insightful? Transistors are not fundamentally thermoelectric devices.

Thermal issues are very important in modern semiconductors, but the switching action of a transistor is not achieved by heating them to change their conductivity. Transistors function by altering bandgaps at the junctions between different semiconductors (or differently doped regions of silicon).

What controls the band gap? Supplying energy to excite atoms and cause electrons to jump to the next shell, opening up holes that increases electrical conduction. What defines the amount of energy in an atom? Heat. What is the measurement for bulk heat density? Temperature. So, as temperature goes down, the heat content goes down, and energy state goes down. The semiconductor becomes an insulator. As temperature goes up, heat content goes up, energy state goes up, and you're now a conductor. Hence, s

Yes. You apply an electric field to the semiconductor, energizing a percentage of the atoms beyond the band gap, opening up holes to allow conduction. You add energy to the system. In other words, you raise the temperature.

I never said it wasn't. I said it dropped dramatically.So much so that the cost difference didn't make the gains from gallium arsenide moot.Then you could through more computers at the problem for less money.Does everyone need every detail of simple concept spelled out for them now?

Yes, that is why I mentioned about fabs. In your haste to seem smart and important, you just let everyone know your ability to deeply understand anything is..lacking.

Except that your comment was lacking in clear referents, which - naturally - created potential for misunderstanding. Especially in the "drop like that" part, it was quite unclear to me whether with the "any process" you were referring to incremental improvements within the existing silicon technology (dropping prices for one silicon switch even further) or whether it was supposed to be progress effected by an arbitrary technology switch (dropping prices for a fast switch in general, for example, the way how

The expansion of carbon does not match the expansion of insulators when the temperature changes. Silicon matches the thermal size changes of silicon dioxide. If Samsung has matched the coefficients of expansion, it is big news. But that was not announced.

The expansion of carbon does not match the expansion of insulators when the temperature changes. Silicon matches the thermal size changes of silicon dioxide. If Samsung has matched the coefficients of expansion, it is big news. But that was not announced.

This insight deserves more than one mod-point! It's the key. For some types of processors or memory size may not be as important as speed or electrical efficiency, but without a compatible insulating layer they can't be built.

There are other high-temperature materials besides ceramic that can be used as the outer casing.

Graphene is an organic molecule, which will have thermal expansion properties more closely related to those of other organic molecules containing aromatic ring structures, because of the bond energies and bond angles involved.

Say, something like aramid.

The only issue with aramid that I can think of is that it cannot be melted. (It has no melting point. It thermally decomposes before melting.) To "mold" aramid, th

Producing them cheaply enough to rival chips made of processed sand is another matter entirely. Anyone remember gallium arsenide chips that were going to eat silicon for lunch back in the 80s? Yeah , well.... still niche.

To a first approximation, I'd say the cost of "applying sticky-tape to coal" isn't very different to "processing sand".

They have to grow silicon crystals too, and it is very complex and expensive to get a pure single crystal, but the source material is readily available and the process has been refined for decades. I imagine that the Gallium Arsenide process you're pointing to is used mostly because it's so similar to what they've been doing with silcon.

What? Only one of those accepts immigration in any significant numbers.

Japan is notoriously xenophobic and does not let immigrants in (hence the crazy search for robot nurses). Korea is only slightly less so. Chinese are generally not as xenophobic as these two, but China has so many people already that there's still a huge outflow of people out of China into all corners of the world.

China is very lax on ex-pats. It is very easy for me as an American to go work in China. It's not quite "immigration", but it does let them build up a big international center. Korea and Japan are straight out. Europe is almost (just?) as bad for the most part.

I think that an article whose author claims that "Germanium... doesn't occur naturally" and that "400Ghz... should make for some strong signals" ought to be taken with a very large lab-grown monocrystal of salt.

I think that an article whose author claims that "Germanium... doesn't occur naturally" and that "400Ghz... should make for some strong signals" ought to be taken with a very large lab-grown monocrystal of salt.

Graphene needed this technological development. It was a pre-requisite for electronics applications, which are currently based on large single crystal silicon wafers. For comparison, this is something that's yet to be achieved with carbon nanotubes, which still have no electronics applications despite being 13 years older than graphene and having excellent properties. People have the same attitude towards graphene: yeah it's great, but it may never be integrated into any mass-produced products and it may just die out and fade away. So if Samsung can grow monocrystalline graphene many inches across, it moves graphene from some pie-in-the-sky research material like nanotubes to something we could actually commercialize. It knocks out one of the big legs from the "Graphene will never replace silicon," argument. Although not all the questions about graphene have been answered, this advance makes those questions and their answers matter a lot more to many more people than they did last week.

Computer/Electronic waste is already such a huge problem that whole companies exist whose existance is to ship that waste to 3rd world countries where they are more or less dumped to contaminate water & soils.
Since from everything I've read Graphene is nearly indestructable.... "It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap [cling film]."
- http://news.bbc.co.uk/2/hi/pro... [bbc.co.uk]

Since graphene is pure coal, it would be rather easy to burn it.I am sure it would be quite easy to make it react with other chemicals to dissolve it. Maybe you could even make alcohol from it? The possibilities are endless. Just because it is mechanically strong doesn't mean it is indestructible.

Graphene is carbon, and the thermal decomposition of carbon as a fuel source has been documented for many many centuries.

A complex designed to thermally decompose the graphene (and any organic substrates it may be bound to), followed by acid and alkaline recovery washes to reclaim the doping agents from the ashes could effectively handle graphene ewaste.

The issue with silicon, is that the thermal decomposition temperature is very excessive,